Method of dyeing strands of textile fibers or filaments



.Dec. 9, 1947. c. GALATIOTO METHOD OF DYEING STRANDS OF TEXTILE FI BERS OR EILAMENTS Filed Ma 5, 1944 2 Sheets-Sheet 1 Edema?" ,& (i ami'iaia VIM Dec. 9, 1947. L. c. GALATIOTO METHOD OF DYEING STRANDS OF TEXTILE FIBERS OR FILAMENTS Filed May 3, 1944 2 Sheets-Sheet 2 Patented Dec. 9, 1947 2,432,404

- IWETHOD F DYEING STRANDS OF TEXTILE FIBERS OR FILAMENTS Luigi 0. Galatioto, Providence, R. I;, assignor to Textron Incorporated, a corporation of Rhode Island 1 i Application May 3, 1944, Serial No. 533,904

2 Claims.

The present invention relates to a method of dyeing a single-running strand of textile fibers or filaments.

In the dyeing of textile materials it is usual practice to dye them either in the form of finished textile goods, as in piece dyeing, or to dye the yarn or thread in the form of wound packages or skeins. For such dyeing operations, large and expensive apparatus is required, large batches of dye liquor are required, and high liquor ratios are customarilyand necessarily employed. Such operations require considerable time to carry them out and to secure a satisfactory result. This is the case because previous procedures require time to eifect exhaustion of the dye while in the dye bath, and vary from one lot to another and one dye to another.

- ticable from the standpoint of commercial dyeing, it would be desirable to dye them without involving dyeing operations separate from the regular manufacturing operations which are necessary.

It is, accordinglyan object of the present invention to provide a procedure for dyeing textile filaments, especially in the form of yarn or thread, without interrupting other manufacturing operations, and which shall nevertheless produce a satisfactory and dependable product, meeting the requirements of the textile industry.

Itlis a more particular object of the invention to provide a method which shall be applicable to both natural and artificial or Synthetic filaments, threads or yarns, such as the various types of rayon, or nylon, with direct dyes. Other objects will appear from the following description.

,In dyeing filaments or yarns it is necessary to eifect complete and uniform wetting of all of the fiber surfaces with the dye liquor. To accomplish this it is usually customary to immerse a skein Or. a package of the yarninto the dye liquor and to pump the dye solution through the yarn, fora considerable period of time, to effect Moreover, the shade of dyeing depends upon the degree of exhaustion uniform and complete dyeing of the yarn by the dye liquor. Otherwise uniform dyeing of the package will not result.

The synthetic textile fibers are commonly obtained in a plastic or fluid condition, when fashioned in the form of filaments, fibers or threads. Consequently, they are subject to shrinkage, upon subsequent drying or setting to a more solid con-.

dition. Such shrinkage leads to more or less firming and slicking of the surface, sometimes followed by a wrinkling of the surface. This wrinkling forms irregularities and fiutings of the fibers, which run more or less longitudinally throughout their entire lengths.

By the present invention it is found that, textile fibers and filaments, both natural and artificial or synthetic, may be dyed satisfactorily at a. high rate of speed, such as that of the usual winding machine operations, without the necessity of re-winding and other handling operations, which have been necessary and customary with suchtypes of textile fibers heretofore. It is also found that uniform distribution, accurate matching of shades, and a high standard of dyed product, by all of the tests usually applied to dyed filaments, yarns and threads of these kinds may be secured by proper selection of dyes, formulatrons and procedures. y

It will, therefore, be readily appreciated that many conveniences and economies may be attained by the present procedure, such as the elimination of the necessity for dyeing apparatus, the large volumes of dye liquor, due to high liquor ratios, the long dryin time required for drying saturated skeins, packages, and the like. The dyeing operation may be accomplished in either small, or large lots, and yet with the facility of quick output and a high quality of product, together'with the economies accompanying each of these advantageous features. l

The process of the invention comprises the discovery that although a filament or yarn may be only capable of being moderately or slowly wetted by a dye solution, it may nevertheless be wetted uniformly and thoroughly by such solution at a high rate of speed by contacting it with a film of the solution, at relatively small points or areas of its surface, under light or moderately firm pressure. "Such filaments may be completely surrounded by such contacting points or areas of film, and if each contactingpoint or area of film'is drawn alongthe fiber surface, or, conversely, if the fiber is run against the contacting film, such film'of dye solution will intimately contact, Wet and associate itself with the surface masses quickly nor uniformly and intimately to filaments of the character here in question, nor at the required speed, with desirable results. Likewise, it would not be adequate merely to run the strand of yarn or thread through a dye bath for this purpose.

On coming from between the Wicks, the filament or yarn 5 is drawn beneath a horizontal, fixed glazed porcelain guide post 26 and thence to a take-up or winding machine so, where it may be wound into tubes, cones, packages, etc. of any convenient size. When these are filled, they may be dried in the usual ways. They will, however, require much less dryin time than similar packages of yarn which have been dyed by the usual procedures, for a less volume of the dye solution may be used upon them than is required by other dye operations. In addition to this factor, the dye solution may be made of substantially any concentration desired, limited only by the dye solubility. By using a more concentrated dye solution, a correspondingly smaller volume of dye solution upon the filament will be suflicient for a iven shade, and yet satisfactory dyeing will be effected, while less liquid is then present to require evaporation in the drying operation.

However, certain limitations must be observed, e. g., to provide an adequate volume of the dye liquor and a sufficient temperature, in order to effect the dyeing during the drying operation, so as to insure the penetration of the dye into the filament, rather than simple evaporation, precipitation and deposition of the dye upon the outside of the filament, Without adequate penetration and fixation. In this way complete exhaustion of the dye by the filament is effected. Consequently, the dye bath solution is not altered during use, in respect of either its composition or its concentration. Hence, a uniform dye liquor is applied in uniform quantities throughout the periphery and throughout the length of the filament. It is completely absorbed and exhausted, in situ, on and within the filament. The dye solution left in the tank is consequently maintained of standard concentration and quality.

In the procedure of the present invention, therefore, the filament, yarn or thread is drawn into intimate contact with numerous freely projecting ends of the fine wool fibers of the felts or wicks. The latter are Wetted with continuous films of dye solution, and as the dye solution is withdrawn by the filament in moving past them, the fibers in turn draw more of the dye film upwardly through the wicks from the dye bath solution 20, by surface and inter-surface capillarity.

The filament, in its rapid movement against or through the fibrous wicks, draws off from the end of each fiber 30 an attenuated film of dye' solution 3| (Fig. 5) and becomes continuously wetted by it. By multiplying the number of fine, separate, resilient, dye-wet fiber ends of the felts, with which the filament 5 thus comes into contact, the pointed films of dye solution thereon will be sufficient to touch every point in the periphery of the filament and wet it. These separately applied, finely pointed films or streaks of dye solution not only intimately wet and adhere to the surface of the filament with which they are contacted, but in conjunction with the rubbing action of the fibers, simultaneously remove and eliminate adsorbed gases therefrom, which escape from between the advancing contact points of liquid dye film. By multiplying the number of these points of dye-wetting contact around the filament, the applied points or films of dye solution not only wet the film surface intimately under the pressure of contact of the fibers from which they are drawn, but also merge together laterally thereafter and thus disperse and distribute themselves over the entire periphery of the filament, including the uneven internal surfaces of the grooves or flutings above referred to, as Well as the smooth, externally rounded surfaces also. As the filament is run through the apparatus at extremely high rates of speed, these contacting and merging films of dye solution coalesce and constitute a rapidly forming and progressing film over and into the entire surface of the filament, in spite of its irregularities and. fiutings, throughout its length.

For example, in one instance of commercial application of the invention, a bright rayon yarn of 300 denier, was drawn from 3 lb. cones and run through the apparatus illustrated in the drawings, and taken up on a usual type of Universal winding machine in 12 oz, packages at a speed of 325 yards per minute. (With higher denier yarns or threads a somewhat lower rate of speed may be desirable, or higher speeds of the yarn may be employed by using wider wicks, etc.) The dyeing solution used was made up in aqueous solution as follows:

Grams per liter Glaubers salt 1.00

The dye liquor in this operation was taken up by the yarn in the proportion of about 70% of dye solution upon the weight of the yarn treated. The wound spools were dried in usual dryers at F. in about 10 hours. The resulting product was not only satisfactory by all commercial tests, but also in respect of matching the shade required. The procedure was conducted at the usual Winding speed so that no slow-down in the operation was required in order to effect completely satisfactory application of the dye solution to the filament at the usual rate at which it was taken up by the windin machine. Complete exhaustion of the dye substance was effected upon drying so that the yarnwas truly and evenly dyed.

A darker shade, as, for instance, a blue which is used at this time for the electrical wire trad was obtained by using a solution of:

Grams per liter Chloramine Blue 3B 8 Chloramine Blue 2B (Sandoz Chemical Wks.) 2 Glaubers salt 1.5

It may be remarked that whereas Glaubers salt is frequently added in dye bath procedures, in order to promote the exhaustion of dye from the bath by the goods, toward the end of the dyeing operation, the Glaubers salt is here already present in the dye bath solution as it is applied to the yarn. By so doing, a film of dye liquor of uniform composition is applied, containing both dye and Glaubers salt in appropriate proportions in the solvent so that, durin the wetting penetration and even distribution over and into the filament, it becomes competent also to be completely exhausted by and into the yarn, to be fixed and developed therein, and then to give up its volatile solvent component or components, during the usual drying operations, leaving a truly fast dyed filament, yarn or thread, as contrasted with a deposit of dye 0n the surface on1y,which may result from excessive dye or too rapid drying, or migration of dye, in a saturated cone or package, which may occur in accordance with procedures of the prior art.

I claim: 1. A method of dyeing textile filaments, yarns and threads, which are characterized by being wrinkled with longitudinal irregularities and flutings in their surfaces whereby they are rendered resistant to quick wetting by the dye solution, comprising the steps of running a strand of the same longitudinally between and in contact with two surfaces of a fibrous material, each surface having a multiplicity of resilient, fine-pointed, outwardly projecting fiber ends disposed in closely spaced apart relation to each other in fine, separate contacts with the surface of the running strand and supplying dye solution to the material, whereby films of the dye solution on the ends of the projecting fibers are severally and intimately contacted with the strand and drawn longitudinally thereof to eiiect a uniform wetting contact and distribution of the dye solution on the strand.

2. A method of dyeing textile filaments, yarns and threads, which are characterized by being wrinkled with longitudinal irregularities and flut- 8' ings in their surfaces whereby they are rendered resistant to quick wetting by the dye solution, comprising the steps of running a strand of the same longitudinally between and in contact with two surfaces of a felted fibrous material, each surface having fibers disposed in thickly and closely packed capillary relation to each other and also having a multiplicity of resilient, fine-pointed outwardly projecting fiber ends disposed in closely spaced apart relation to each other in fine, separate contacts with the surface of the running strand and supplying dye solution to the material, whereby films or the dye solution on the ends of the projecting fibers are severally and intimately contacted with the strand and drawn longitudinally thereof to effect a uniform wetting contact and distribution of the dye solution on the strand.

LUIGI C. GALATIOTO.

REFERENCES CITED FOREIGN PATENTS Country Date Great Britain Feb. 8, 1932 Number 

